Molecular phylogeny and morphology reveal two novel entomopathogenic species of Hypocreales (Polycephalomycetaceae and Cordycipitaceae), from China

Based on an integrated taxonomic approach combining multi-locus phylogenetic analysis and morphological characterization, we formally describe and illustrate two new entomopathogenic fungal species from China, Pleurocordyceps longiphialis and Samsoniella aggestitenuipes. Phylogenetic analyses of a six-locus dataset (ITS, nr SSU, nr LSU, tef 1 - α, rpb 1, and rpb 2) strongly support the distinct phylogenetic positions of the two new species within their respective genera.

Morphologically, P. longiphialis, isolated from a Scarabaeoidea larva, possesses notably elongated α-phialides (9.5–101 µm) and dimorphic conidia. In addition, S. aggestitenuipes, obtained from a lepidopteran pupa, displays synnemata with powdery conidial masses and phialides measuring 6–28 µm. This study also reviews the host ranges and geographic distributions of Pleurocordyceps and Samsoniella.

Pleurocordyceps species are known to infect insects in Coleoptera, Hemiptera, and Lepidoptera, and also parasitize fungi such as Elaphomyces, Ophiocordyceps, Paraisaria, and Perennicordyceps. Samsoniella species have been reported from Lepidoptera, Coleoptera, Hymenoptera, and Arachnida. Geographically, Pleurocordyceps occurs in Asia (China, Japan, and Thailand) and South America (Ecuador), while Samsoniella is distributed across East Asia (China, Laos, Thailand, and Vietnam), Europe (UK and Ireland), and South America (Argentina).